This function will bring up an alert box to show the last error that occurred due to a server request, including an error returned from an SQL statement used to load a database-driven widget.
If there has not been any errors, this function will show "No errors reported".
The difference between this API and the showErrors() API is that this only shows the last that occured, whereas showError() will display all errors since the last time screen was re-displayed.
The typical use for this API is tp show SQL errors during an "ondbload" event for a database-driven widget. For an example, see the ondbload event.